Note: Descriptions are shown in the official language in which they were submitted.
` 21S3~76
1 g5/1340~ PCT/C~g4/00217
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DE~l OE AND PROCRR~ FOR T~X ~LECTROLYTIC B~PAR~TION
OF METALS WIT~ AID OF A RO~ATINE CA~4v~ SYS'~EM
The in~en~ion perta~n6 ~o a device for the elec~ro~y~ic
separ~tion/depo~ on.~f meta1s w~th ~he ~id of a rotatin~
ca~hode ~yste~ and a pro~e~s for the operat~on of the device
~a~ording ~o p~ten~ claim 1 or lD.
Electroly~is devlce~ are ~o~n for the ~eparation o~
metal~ ~ro~ solutio~, in wh~ch the e1ectrodes ~re ~rranged ~
pl~es in packe~-fo~m. Thi~ cau~e~ of~en the ob~erv~nce ~f
~hor~ or, due to faulty cont~ct~, uncontro11~1e ~u~en~
den~itie~ o~ur (o.1 - 1 amp/dm2) that cau~e ~i~e and time
again ~aryi~g depo~ition~, Furtherm~re, the $1~w condition~
are di~ficulf to control, reæultin~ ~150 in inhomogeneou~
deposition~. In order to compen~a~e ~or ~he~e disad~ant~ge~,
lower current den~itie~ are employed ~ha~ result in long
deposition ~i~e~ ~nd, t~erefore, be~ame economically
undeslra~le, o~ larger $n~t~11at~on~ are employed, re~ulting
ln addi~ional C08tS for the in~tall~tion.
A~c~rding to P~-US 5,1g3,544, a met~l recovery sys~em i~
known ~hat allo~s th~ ~etal recove~y from fil~r c~kes~ In a
pretre~ent, the metal-cont~ining ~ilte~ cake p~r~ ~re
b~aught into ~u~pension and ad~ed to an ele~t~olyte in which
the metal~ a~e preclpithte~ on~o a rotating c2tho~e. Th~
~at-hoAe i~ a nickel-~o~ered or chrome~covered ~luminum. It
must every ~i~e be provide~ in a ne~ly prepared fonm, which i~
~$s~vantageou~. Furthe~more, the cathode has to be wo~ked up
~fter co~ple~ed depo6itlon Pefore i~ c~n be returned to t~e
p~o~e~.
It i~ the puxpo~e of ~he present invention to disclase a
.,
21~3S76
~ 95/1340R PCT/C994/00~17
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device for the ele~rolytic deposition of metal6 an~ a p~oces~
for it~ operation which pxovide a rotat~ng ca~hode sy~tem that
is of c~pa~t design an~ simple to operate, p~ecipita~es ~he
metals compa~ly and homo~ene~usly and, therefore, ig
particularly ~uitable ~or metal r~o~ery.
Accor~ing to ~he in~ention, thi~ ~oal i~ Rchieved wit~ a
~eYice acco~ding to the ~ord~ng of paten~ claim 1, and a
pr4ce~s acco~ding to the wording of paten~ clAim 10. In claims
- 9 a form o~ execu~ion for the~e i~ ~i~en, The invention 1~
in the follo~ing descri~e~ in ~ore deta~ls on ha~d of ~he
dr~wings. Depicte~ a~e by:
Fi~. 1 Prin~iple o~ the ro~ating ca~hode ~y6te~ in an
electroly~i~ unit in schemat~c depic~ion
ig. ~ Par~ o~ a ~uppor~ cylinder in ~ection wit~out
cont~c~ ~od
Fig. 3 P~rt o~ a ~uppor~ cylin~er in ~ection after
intro~uction of ~he contact ro~
Fig. 4 Exa~ple o~ form of exe~ion o~ a confac~ ~h~ber
~ig. 5 Example o~ form of exe~ution o~ a ~an~le ~thode a~
a(n) ~ontinuous/en~le~ ho~e.
Fig. 1 ~epicts ~he prinaiple of ~he ~otating cathode
~y~te~ in ~n electroly~i~ un$~ s~hematically. on a
BUppO~t/inst~ $on f~me 1 i~ A contain~x 2 ~$~ua~ed ~ha~
cont~ins ~he electrolyte 3, an~ int~ whl~h a cylindrical pipe
4 i~ wel~e~. A drive ~haf~ 5 i~ ln~erte~ th~ough this pipe and
sup~or~e~ by the be2ring~ ~ and ~' an~ thk~ ~ ~ dri~en by an
.
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95~13448 , PCr~C~9~/00~1
adjustable drive 7 wi~h ~he a~d of a ~e~r belt ~ and at i~
upper end is equlpped ~i~h ~ flange 9. T~e pipe ex~ends aboYe
the level 1~ of ~e electrolyte, wh~reby a run-off of ~he
electrol~e is prevente~. ~he electroly~e~ unit i~ fed with
the electroly~e or re~pectively e~p~ie~ ~h~o~gh the inlet 17
or t~e oYerflow 18. ~herefore, ~he device i~ al~o ~uit~ble for
~asc~de arrangemen~ of se~eral such unit~.
The ~ive shaf~, here, e.g., con~ructed ~s a hollow
sha~t, con~ucts the current flow on the cathode ~ide, f4r
wh$~h a sliding ~o~y 10 is pro~ided. ~he drive ~h~f~ req4ires
a ~ertain rigi~i~y ~nd - in ca~e it $~ supp~ed to ~erve
51mU1t~neOU~1Y a~ cu~rent fee~ is ~nufacture~ ~rom a ~e~a1
a11OY ~U~h ag har~ bronze or hard ~o~e~. If the dri~e 5haft
i6 ~e~igned as a hollow Bhaft~ it ~, e,g,, m~de of Stain1e~
~tee1, WhiCh h~S a PO~$~$Ye ~nf1UenCe On the 40r~0sion
PLOYe1LieS~ The power fe~d 19 may then ~e h~ndled ~y a coppe~
con~u~t~r. Attache~ ~o ~lan~e ~ i~ a ~u~LL cyl inA~r 11 ~0
that it~ CY1inder wall~ ip ~n~o the electrolyte. ~n ~he
out~ide o~ ~he ~upport oyl~nder a mantle catho~e 20 is
~astened, to wh$ch ~-~e current ~upply 19 occu~ oYer a con~t
rod 30 w~h a ~ocket 14, ~s is de~cribed fur~er down. Ihe
current s~pply on t~e ano~e ~t~e accur~ in knawn m~nner wi~h
b~r electroae~ o~ plate elect~o~ee 15. Suitable ma~erlal~ for
the m~tl~ CathOde 20 are foil~, ~a~zes, webs, braia~, ~on-
wo~en~, foam or similar o~e~ of ~e~al ar plastic.
~ ig. 2 depicts a part of a ~uppor~ c~linder in ~ec~ion.
Support cyl~n~er 11 ~5 provided with ane o~ ~everal n~rrow
~l~t~ ~1, into wh~ch the ~a~le ~hode 20 i~ fi~ted so that
~ts ends 22 and 22' are g~ded around the edge~ 23 ~n~ 2~ 1 o~
the ~uppor~ ~yl~nder. ~he ~ L cylln~er ~ preferably made
4~ plastic, e.~., p~lypropylene. Howe~er, it ~ay al~o ~e
` 2153576
5/13408 pcr/c~94~00217
manuf~ctu~e~ O$ a me~all~ ~aterial and may on it~ ~n6ide, a~
le~s~ up to above the ele~roly~e level, be co~ed with
re~in pow~er ~o mee~ the requirement~ o~ In~ulation an~
~o~rosion. The 61Ot~ 21 a~e n~rrow an~ u~ed ~o the
~ter~al of man~le catho~e ~0. They ~e Z-53m wide and extend
e~entially p~rallel to the r~t~lon ~xis of he ~ri~e shaft;
howe~er, they may al~o be arranged at an oblique angle.
Suit~le mantle catho~ re ~hin~ flexible material6, e.g.,
~u foil~ with a ~hickness o~
15-150 ~, preferably 70 ~m, or ~ pol~o~ylene ~e~e of
50-500 ~ m thi~knesg, or an electr~cally ~o~ cting
pol~ropylene foam wit~ a thicknes~ of 3-5~m that i open-
porous ~nd has low o~m~c reslstance. such ~antle c~t~o~e
mAte~ial6 are economi~ally availa~le in rolls. ~he m~ntle
~atho~e piece6 are cut in~o ~ections for the pu~po~e of being
loaded onto t~e support cylinde~, ~n~ are at t~e~r ~nd~ ~cut
off'~* so that t~e cante~-o~f e~d~ ~the selvage)* can ~imply be
laid into t~e ~lo~. Af~er insertion o~ a contact ro~ - a~
de~cr~ed further down - result~ ~uch a ~antle ~a~ho~e ~hat
lies ~lat on the 6uppor~ ~ylin~e~. There~y is an exactly
~efined geometry glven ~or the ~node conf$gur~$on, Wh$~h i5
e6~n~al for a h~mogeneous depos~tion. The 61Ot width6 ~re
no~ selec~e~ f~r the cho~en ~an~le ~thode ~aterial~ ~ch ~hat
deposit~on ~ effecti~ely prevented behind ~he slot. ~eh~
slot 21 is situated a contaq~ ohamber 25 ~ha~ ex~en~ p~rallel
to the ~lot an~ i~ fox~ed by profile 2~ and support ~ylinder
11. The prof$1e ~ $s f~stened to the;s~pport cylinder at
poin~ Z6 a~d 26', pre~era~ly welded on. ~ontact chamber 25 i~
he~e in~icated in a ~quare fo~m and iB ~ntende~ ~or
contactin~. i
Flg. 3 dep~cts a part o~ the ~uppor~ cylinder $n section
a~ter in~e~$on of the ~on~ ro~ . SU~OL L cyl~nder ll and
2153S76
~ ~/13408 PCT~CE94/D021
m~n~le ca~hc~e ~0 with the end~ 22 ~n~ 22~ ~ond ~o ~ig.
. The con~act chamber 25 i~ here es~ent~ally cylindrical an~
is ~ealized by a pipe 24. The con~act rod 30 effects the
es~abll~h~ent of contQct with mantle cathode 20 fo~ the
current fla~ on ~he cathode 6$de. ~a~er~ al ~n~ dimen~ions of
the contaat rod are 6electe~ ~u~h ~hat contact i~ m~de o~er a
la~ge ~urfa~ 8~ea an~ the ~lxation of ~he m~n~le cathode on
the support cylin~er can simul~aneously occur without need for
a~itional means ~or their fixation. ~ ha~ ~CUV~l. to be
especially a~v~n~ageou~, o~taining ~he h~ghes~ eleçtrolyte-
specifi~ curren~ ~en~ities, pre~erably 1-10 ~p/dm2, ~nd
re~ult~ng ln 8 c~p~ct, mechanl~lly s~ etal layer
without o~ervation of digtur~ed depo~i~ion~. contact ~od 30
w~ s~lected w~h a ~rcular cxo~ ~ection, but may al~o ha~e
a cro~ 6ectio~ deviating ~rom ~hi~, e.g., a hexagonal one;
es~enti~l is tha~ through the choice of ~teri~l and
~men~ion, ~pecifically dia~e~er and ~hape of ~e cro6fi
sectlon, ~n op~lmal force~ contact-maktng is ~chieved which ~s
ma~ched/ad;us~ed ~o the applied m~te~ of the mantle
~a~hodet Surpri6ingly, the u~e of a con~a~ ro~ o~ the
described kind resulted ln a co~pletely tensioned mantle
catho~e - al~o w~th u6e a~ razor-th~ n foi~ - that laid fl~t
on the suppo~t cylinaer. Furthermo~e, ~he ~n~pulation o~ this
form o~ ~astening proved ~-o be t~ou~le-free, OEimple and f~t,
~onflrme~ by a goo~ reproducibility of ~he ob~ine~ depos~t~.
Fig. 4 depict~ an example of execu~ion o~ ~ contac~-
chamber~ A ~e~o~ ~yl~n~er 40 lc loca~e~ hP.~t~ ~upport
~yl~n~r 11, h~ing a ~;maller di~e~er ~h~n support; cylln~er
11~ The inner c~ylinder 40 i~ coImecte~ to ~uppor~ ~yl~nde~ 11
over the connect~ng s~r~ctures ~Pri~ge) 40 ~n~ 41'. Th~
c~ea~es ~ ~on~aqt cham~er as tha~ LS ~f ~pproxim~te~y s~uare
or rectansular for~, in whi~h the mantle ~tho~e ~O can be
2153576
O 95/13408 PCT/~94/00~17
brou~ht in contact wit~ a s~uare or red~angul~r ~on~ac~ ro~over a l srge t:ur f ace area .
Fi~. 5 ~epi~ an example of execution cf a m~n~le
~a~hude ~ a ~ontlnuou~ ho~e. Here again, ~he con~act chamber
~5 wa~ created ~ith a pipe z4. As man~le ~a~ho~e ao a ho~e-
~hape~, ne~-llke ma~er$al ~a~ u~ed that i available ~ an
endle~s ho~e and i8 cut into piece~ accor~ng ~o t~e
~pplication. ~he cu~ ho~e piece 15 pulled over s~p~or~
cylindex 11 and with a plate 5~, ~erving as an in~allation
~ool, p~hed in aire¢t$on o~ the arrow into the ~lot ~o ~ha~
after remo~al of ~he installa~ion plate cont~ct can be
~hieve~ in a ~ple and a~ured manner. Preferen~l~lly u~e~
f~r ~his example of execu~i~n are ~u~o.L cylinder~ with
~iametr~cally oppo~ed ~lots, re~ul~ing ln ex~ellent contact
and guaranteea flat 6urface~ o~ the mantle ~athode~ By the
appl$ca~ion of a ~econd slot ~g su~h a~hieve~ a ~requently
desi~ed doubling of t-h~ con~ urface.
Example 1 ~e~cri~ an electroly~l~ o~ a ~olution of a
c~-cont ining st~n~ng rinse b~th tha~ ha~ ~een ~n~talled
~ollowing a Cu electrolyte wlt~ 60 g/l ~opper. Used as ~nkle
cathode wa6 a 70 ~ cu ~oil wi~h ~he mea~ure~ent~ 0.25m x
o.438~ an~ a catho~e ~urface o~ 0.344m2. The ~a~hode ~y~tem
rotated a~ 1~ rpm. ~urrent de~ity was approxim~ely 1
amp/dm2~ T~e ba~ch ~olume waOE loO 1 with a s~r~$ng
concentration o~ 4 g/l. The end concen~r~t~on after 15.3 hrs
wa6 apprax. 1.2 mg/l, in~icatlng ~ ~e~ree of ef~iciency of
64~.
Example 2 ~cr~ec an electroly~ f a ~olut~on o~ an
Ag-~ontainin~, cy~ni~e-~ontaining sta~i~na~y rin~e ~ath,
~ituated ~ollowing an A~-cyanide ele~roly~e. As man~le
_~ 95/134~B 215 3 5 7 6 PCT/CEg~/00~17
cathode was ~gain a 7 ~ Cu-foil u~ed ~h ~he mea~ur~ments
0.25m x 0.43B~ an~ a ~athode surf~ce area o~ 0.344m2. ~he
c~ho~e Gy~e~ rotated at lG rpm. current den~ty ~ae
approxim~ely 1 amp/dma, The ba~ch volume wa6 loO 1 ~th a
~tarting concen~ration of 1.74 g~l. The en~ concentration
after 13.8 hrs was approx. 1.5 mg/1, ~ n~; CA~t ng a ~e~ree o~
eff~c~ency of 9,1~.
Example 3 des~ri~es an electrolysi~ o~ a ~olution of an
~g-~ontain~ng, cyanlde-con~in~ng ~tat~ o~ry rin~e bath
~itua~e~ following an Ag-cy~ni~e elec~rolyt-e. A~ man~le
catho~e wae again a 70D~ cu-fo~l u~e~ with a cathod~ ~urface
ar~ o~ 7 ~m2, The cathode ~y~tem rotated at 16 ~ The ~atch
volume w~ ~0 1 with a ctarting ~on~entr~tion o~ 1.74 g/l. T~e
en~ ~oncentr~tion a~ter 49 hr~ was approx. 1 mg~l, indi~a~in~
a degree of effici~n~y ~f 7%.
Exa~ple 4 de~r$be~ an electroly3~ of a ~olution of a
Cu-conta$ning bath con~aining a ~uS0~ electrolyte wi~h
14 g/l copper~ The ~an~le cat~ode had a ca~ho~e ~u~face a~
35dm2 ~nd was rota~ed at 3~ L~ he bat~ valume ~a~ 12D 1.
current dens~ty w~ app~ox~mately 1.5 amp/dm~ at a c~11
cu~rent of 52 amp. The ~tarting con~entr~tion was 14 g/l, the
en~ ~Q~C~ntra~ion af~er ~8~5 hr~ wa~ ~elow o~lm~/l, ln~ica~in~
a degree o~ eff$c~ency of 95.7%.
Example S de~cr$be~ an elec~roly6i~ of a ~olu~lon of an
Au-contain$ng ~ath with ~ g~art~ng Goncentrat~on of ~CO
gold. The mantle c~thoae had a cathode ~urface area o~ 7.3 dm~
and a ~ota~$o~ speed af 1~ ~pm. ~ath volume was 30 1, pH-value
~a6 4.5. The curren~ ~en~ity was ~pprox. o.L amp/d~2 at ~ cell
curren~ o~ 0.73 A. The anode~ ~here pla~inized titaniu~. The
electrolyte ~low ~a~ ~rected on~ the cathode, ln~rea~ing the
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95/13408 P~T/C~9~JOOZ17
agita~on of ~he elec~olyte. The ~inal concen~ration af~er
16 hrs w~ approx. 1 ~ ndicating a de~ree o~ eflftciency
of 13.9%. In total, 12 g gold were deposite~ in thin
6epar~tion ~orresponain~ to 1~02 gta~pere hour~.
The device and procegs o~ t~e des~ri~ed ~ype f in~
application in the (wa~te) remo~al of metals from metal-
con~ning colutlon6 h~vin~ ~u~iciently high ele~trical
conductivity ~ut al~o ln the ~eple~ion o~ suoh solu~ion~ for
the purp05e of recycling them after a certain time of
ele~tr~lytical treatment b~ck into the wo~k proce~. Thi~
e.~., of intereet in et~hlng B~lution~ ~nd electroly~e~ of all
kin~s that change ~uring ~he ~ork pro~e~5, which ~an lead to
un~e~ira~le metal concentratlons.
E~e~tial for the invention ig th2t ~he inventive
~olut~on to the problem 1~ di~tingu$shed by a ~imple han~ling
of the B~pport cylinder wi~h mantle cathode, e~pec~ally ~n
regard ~a ~he removal o~ the elec~rolytic~l depogit ~rom the
m~kal cath~de, and ~y the choice o~ the m~ntle c~t~ode
m~erial, s~ nce 'che latter ~an be opti~lly ~ailo~ o a
p~icular ~lec~rol~ic deposltlon.
